I'm not talking about going alone and unarmed, but going back with backup and weapons. After all, she seems to think that a small sharpened object can hurt it (she tried to use that for self-defense).Why would she think that she could destroy it? She barely survived the last time.
BTW what ever was hunting her was able to scent blood, as she covered her scratches in mud to avoid capture
Given that, she may very well think (and maybe correctly) that guns, machine guns, energy weapons, explosives or some other thing in SHIELD's arsenal would do it.
But again, I'm speculating here. Maybe that's not why she wants to go back. I'm just suggesting a potential motivation.